1. Field of the Invention
This invention relates generally to computer peripherals, specifically to an ergonomically shaped computer mouse.
2. Prior Art
Many software programs use movable cursors for selecting data and objects or drawing on a display monitor. The cursors are generally controlled by a manually manipulated pointing device connected to a computer. Common pointing devices include the mouse, trackball, touch pad, and digitizing tablet.
The mouse is the most popular pointing device. It includes a housing that is slidably moved about on a flat, stationary surface. The housing contains a motion sensor on its bottom side for tracking its movement, one to three buttons on its front edge, and electronic circuitry for communicating with an attached computer. When the mouse is moved about, the cursor moves in corresponding directions; and when the buttons are pressed, certain actions can be performed, depending on the software application using the mouse. The internal parts, and electrical and software operations of computer mice are well known in the art.
Most mice, such as the one shown in U.S. Pat. No. D302,426 to Bradley et al., are substantially wider than they are tall, and have generally symmetrical sides so that they can be used by either the right or the left hand. Some mice are specially shaped for providing an optimal fit for a user's right hand. The mouse shown in U.S. Pat. No. D328,597 to Clouss, and sold under the trademark "MouseMan" by Logitech Inc. in Fremont, Calif., has a slightly angled but generally horizontal top surface for supporting the fingers and palm of a right hand. The Microsoft Mouse, Version 2, sold by Microsoft Corporation in Redmond, Wash., includes a concave left side for closely engaging the base of the thumb and palm of a right hand. The mouse shown in U.S. Pat. No. 4,862,165 to Gart includes a surface for supporting some fingers in substantially curled positions. Some ergonomic mice, including the Logitech MouseMan.TM., are also made in left-handed versions.
All prior art mice have a generally horizontal, primary supporting surface for supporting a hand in a horizontal position, as exemplified by the drawing figures of U.S. Pat. No. 5,157,381 to Cheng, and the drawings in the user's manual of the Microsoft Mouse. However, the most natural and relaxed position for a hand--when placed on a desk by a sitting person--is an upright position: the little finger side of the hand rests on the desk, and the fingers and palm generally define a vertical plane. Therefore prior art mice force the hand, wrist, and forearm to be twisted 80 to 90 degrees out of their natural and relaxed positions, and require constant muscular force to be applied to the hand, wrist, and forearm to maintain their positions. For a three-button mouse, the fore, middle, and ring fingers must be kept in constant tension to prevent them from resting too heavily on the buttons and depressing them inadvertently. A horizontal hand holding a prior art mouse is supported on the desk by only a small area at the wrist on the little finger side, so that a pressure sore may develop thereon. The total effort and discomfort may not seem great at first, but when these mice are used over a prolonged and continuous period of time, users may experience fatigue, discomfort, and even pain in the hand and wrist.